A rapid IgM antibody capture (RMAC) ELISA using enzyme labeled one ofthe species specific McAb 2H_4 as tracer was studied for the early diagnosis.The antibody thus obtained was confirmed specific, because it was destructableby 2-ME, could be blocked by JEV antigen, and had no cross reactivity with HFRS virus or adenovirus IgM antibody positive sera, as well as was notinterfered by RF. 10 serum specimens were tested for JEV-IgM by conventionalMAC-ELISA and RMAC-ELISA simultaneously, and the Iatter one was mo...